Digiscoping

On loading my camera with a sigma 150-500 zoom plus a spotting scope, binoculars, tripod and fluid head into a backpack I found my legs buckling and realized carrying all this lot around is totally impractical, so I either leave the camera behind or try digiscoping. At home I tried just holding a 50mm/f1.8 over the eyepiece (it's a perfect fit to the Hawke Endurance ED eyepiece) and found the results at minimum magnification pretty good but very dark at maximum. I know the optimum solution would be a Pentax digiscope with the dedicated adaptor but the latter is £299.00 and as far as I can see replaces the eyepiece. For about £30.00 I can get a Hawke fitting with a T2 thread which just clamps to the eyepiece, and I would attach the camera with a T2 adaptor. Now, the standard option is a T2 to K mount adaptor, so the camera is mounted directly, or alternatively I could get a T2 adaptor with a 52mm thread to fix to a lens. I can see the logic in eliminating any glass between the eyepiece and the sensor but as the camera body would just be pressed against the rubber eyepiece I would be really worried about the lack of a good seal to protect the camera innards. Does anyone have any experience of such a set-up? I would be most grateful for any advice or comments.

Cost versus items such as: weight, apertures and optical abilities of the glass.

Unfortunately the bigger and heavier the glass is; typically the better it is; optically and typically on the aperture side as well. Yet it is also based upon the sensor; that 150-500 reaches out considerably more on existing Pentax NON full-frame (by having the 1.5 magnification factor) than any existing (typically 24x36) sensor.

There are a few items in the way of alternatives though...

Depending upon the type of spotting scope; if one can find a reliable metal shop - one can have an adapter fabricated relatively inexpensively. The existing Pentax converter for spotting scopes is expensive, but... Also compare that price to items such as the existing top end Pentax teleconverter. BTW that Pentax converter for use in spotting scopes will outlast any other Pentax hardware.

Consider too, that... The focal length range of a number of spotting scopes. Some easily exceed some 2000mm focal length when attached to non full-frame cameras. The aperture will be terrible. But also feel welcome to compare size and weight to a real telescope, such as my Meade 20" telescope.

More about the Pentax teleconverter... Depending upon ones digital body... That Pentax teleconverter is an above average option, but one will lose a considerable amount of optic ability and also a bit of aperture. Consider a comparison between a teleconverter and even a cropped image. For cameras such as the K3 (with most subjects) the cropped image will typically be better than most any teleconverter

The Hawke adaptor has finally arrived (no instructions), comprising two parts which fit together, one on the scope eyepiece and the other on the camera. The eyepiece needs to be unscrewed to fit the scope part but could be left on and still used conventionally. With the T2/K mount adaptor the other part fits on the camera body and presses it against the rubber eyepiece. This of course risks exposing the camera to dust which is why I tried it with a 50mm f1.8 len attached but the results weren't promising. The other thing I tried was a 2x teleconverter on the K-mount to protect the camera but the loss of light meant high noise; the best results were from the direct mount. One concern is that the T2/K-mount adaptor has printed lettering on the T2 face which is coming off in tiny particles when screwed into place so I have been rigorously cleaning that to avoid it contaminating the camera, hopefully by leaving it permanently attached to the digiscope adaptor this won't become an issue.

I had hoped for a system whereby I could use the scope conventionally and then quickly snap the camera into place and in truth it's not much more involved than changing a lens. Two issues however; the scope needs refocusing with the camera on, and the weight of the camera unbalances the scope mount so a sliding tripod mount will be needed (more cost, more weight). The scope has an 18-48x zoom but the loss of light at the high end becomes much more apparent with the camera attached. Also without a lens the anti-shake is off.

I am looking forward to trying it out properly.

I've found the same issue in properly mounting the camera to the scope.

It's almost as if "they" want us to purchase the more expensive adapter and then also a Pentax scope.

Manfrotto sells metal clamps and adapters that work with most setups. If that does not quite work, also browse through studio lighting adapters, still ensuring that they are also metal. Even multi platform adapters that would typically be used for two cameras, even c-clamps.

Why metal? Anything outside of metal and/or carbon fiber simply risks breakage, of camera and/or scope.

I have resolved my problem with the vulnerability of the open camera body when fitted with the digiscope adaptor, by I modestly claim, a stroke of genius! The K-mount/T2 adaptor which you need to fix the digiscope adaptor onto the camera body can be dismantled into two parts, so into this I dropped a 49mm UV filter glass which is a perfect fit. Reassembled it is now like a thick filter which I can leave on the camera body ready for the digiscope adaptor. The trickiest part was getting the glass out of the filter frame without scratching it - it was held in with a sprung ring so some judicious work on the frame with a tinsnip was needed to remove it.

And here's a special thanks to the guy at London Camera Exchange in Leamington Spa to whom I explained what I was after. He rummaged around and gave me the filter from his 'spares' box at no charge to experiment with.

WARNING! Tried my digiscope set-up this week with the K-mount/T2 adaptor in place. As soon as I looked through the viewfinder it was filled with large black specks which can only have been paint flaking off the adaptor. Most of them were inside the housing on the mirror and focusing screen but a couple had got on the sensor, which all came away with a blower. However some had also somehow got behind the focusing screen which I very carefully took out when I got home and managed to clean behind, again with a puffer and a very soft brush. Bearing in mind the camera had been professionally cleaned before the trip you can imagine I was spitting feathers!

You can see clearly where paint has come off the adaptor on the K-mount part as well as the opposite face and I will be contacting Bristol Cameras where it came from but it will be consigned to the bin.

The other issue was that the adaptor is in two parts held by grub screws, which came loose whilst handling the camera on the tripod-mounted digiscope causing the camera body to wobble. So not a great start.

Here's my first attempt at digiscoping with the aforementioned kit. I haven't done any sharpening, this was shot in live view at about 30x magnification, in aperture priority and manual focus. Even mounted on a tripod it was tricky to keep the image steady so don't know whether the lack of sharpness is the set-up, my eyesight or camera shake. Zooming in live view wouldn't render it any sharper. The image in the digiscope without the camera was pin sharp but needed refocusing with the camera in place so a bit of a chore.

In conclusion this is useful for checking bird identity but the whole process was pretty cumbersome and the problems I mentioned before spoiled things, so I only really started to enjoy myself when I put the camera away and observed the wildlife through binoculars. Maybe better with a small compact camera.

20 inch telescope! Wow.